Toothbrush

ABSTRACT

Toothbrush comprises a handle and a head, said head comprising upstanding bristles and at least one upstanding tooth polishing element, characterised in that the tooth polishing element is in the form of a resilient wall-like member and is flanked by bristles.

[0001] The present invention relates to a toothbrush according to thepreamble of claim 1.

[0002] Toothbrushes which aim to provide a benefit in addition tocleaning are known in the art. In particular, toothbrushes which aim toprovide a tooth-whitening, polishing or gum massaging effect arewell-known.

[0003] WO 98/18364 (P&G) describes a toothbrush with combination ofbristles, soft cleansing pad and/or polishing fingers. The polishingfingers are preferably made of a thermoplastic elastomer and the softpolishing pad is an absorbent pad capable of providing an improvedcleaning benefit.

[0004] GB-A-2 040 161 (Vowles) describes an improved toothbrushcomprising, in addition to conventional bristles tufts, a gum massagingmember located outermost on opposite sides of the brushing surface.

[0005] WO 98/22000 (Asher) discloses a toothbrush comprising a plaqueremoving member being formed from a mixture of relatively softelastomeric material and particles of an abrasive material.

[0006] Despite the presence of such brushes in the prior art there isstill a need for a brush which is capable of providing an improved toothpolishing benefit and is still capable of cleaning the teetheffectively.

[0007] Accordingly, the invention provides a toothbrush comprising ahandle and a head, said head comprising upstanding bristles and at leastone upstanding tooth polishing element, characterised in that the toothpolishing element is in the form of a substantially resilient wall-likemember and is flanked by bristles.

[0008] Preferably the toothbrush is a manual toothbrush and not anelectric toothbrush.

[0009] It is an essential feature of the invention that the wall-likemember runs for a substantial distance and is not a mere rubber fingeror flap, arcuate or otherwise.

[0010] The wall-like member is preferably made from a material softenough to provide a polishing benefit to the teeth and so it ispreferred that it is made from a material with Shore A hardness ofbetween 5 and 80, preferably from 15 to 50.

[0011] The wall-like member provides a polishing benefit as it is rubbedalong the surface of the tooth during brushing. Due to its wall-likestructure and its resilient composition it is capable of beingelastically deformed and this helps provide the polishing benefit. Anotable distinction from brushes in the prior art is that the polishingelement runs for a substantial distance along the brush head. This meansthat the element can be resilient enough to not feel uncomfortable tothe user, i.e. too hard, and yet is not so deformable as to be merelymoved to one side during brushing as would happen if it were a rubberfinger. It is preferred that the wall-like member runs for a substantialdistance along the brush head and, preferably, for a distance of atleast half the length of the head, preferably at least three-quartersand especially at least the whole length of the head.

[0012] Where the wall-like member runs for a distance greater than thelength of the head, i.e. the running length is greater than the lengthof the head it is necessary for it to be curved in some fashion. Thismay be a gentle curve but it may also be curved in a snake-like orgenerally sinusoidal fashion, i.e. it changes direction several timesalong its length.

[0013] The running length should not be confused with the straightlinelength which is the shortest distance between either end of thewall-like member. Further, the running length and length of the head aremeasured along the junction between the wall-like member and the head.

[0014] In a particularly preferred embodiment the wall-like member runsan exaggerated meandering path along the brush head so as to provide thepolishing benefit when the brush is rubbed along the teeth in anydirection.

[0015] In an alternative embodiment the wall-like member is tapered awayfrom the brush head, i.e. it is thicker in cross-section at its basethan it is at its tip. This helps to amplify the elasticity of thewall-like member and improve the tooth polishing capability.

[0016] Typically the wall-like member will be between 10 and 40 mm inlength and will extend from the head by from 6 to 14 mm, preferably from8 to 12 mm.

[0017] It is envisaged that the wall-like member can be made by anyconventional method, i.e. die-cut or moulded. However, a preferredmethod of making such a structure would be by injection moulding. Thematerial of the wall-like member may be linked to the head of thetoothbrush in any way whether it be by chemical means, mechanical meansor both.

[0018] In one embodiment the material of the wall-like member ischemically compatible with the material of the head and they may bejoined by application of heat, e.g. during injection moulding of one orthe other.

[0019] In another embodiment the materials may be chemicallyincompatible, e.g. the wall-like member comprising a thermoplasticelastomer such as TPE and the brush head comprising polypropylene. Itmay, therefore, be more suitable to use an adhesive or to mechanicallyattach the two parts to one another. An alternative method of attachingthe wall-like member comprising TPE to a head comprising polypropylenewould be to increase the surface area of the area of attachment, e.g. bycorrugating one or both, and then fixing the two together by welding orotherwise.

[0020] In a preferred embodiment the wall-like member is attached to thehead through an aperture in the head which corresponds to thecross-sectional shape of the wall-like member, the member beinginjection moulded into the aperture.

[0021] It may also be that the wall-like member is contiguous withanother portion of the brush comprising the same material and that bothare filled through one or more injection points. For example, thewall-like member and a grip region on the handle are contiguous througha channel running along the head to the handle.

[0022] In a further embodiment the wall-like member is textured. Suchtexturing may be as a result of the inclusion of abrasive to provide anextra cleaning benefit or the wall-like member's surface may bedeliberately roughened.

[0023] An alternative type of texturing can be produced by including aridge to the wall-like member, the ridge running along at least part ofthe length of the wall-like member. The ridge may take any course alongthe wall-like member, vertical or horizontal, but, preferably, it runsalong at least part of its tip.

[0024] It is an essential feature of the brush according to theinvention that the wall-like member is flanked by bristles. Suchflanking may be a mere scattering of bristles but it is preferred thatthe bristles are located outermost on the brush head and the wall-likemember is located more centrally. This is a particularly beneficialdesign as it allows the teeth to be cleaned while also allowing theteeth to be polished. The bristles are flexed outwardly to allow thewall-like member to contact the teeth and this further improves thecleaning efficacy of the brush. Should the wall-like member be locatedat the outer edges of the brush head the flexing of the bristles wouldcompromise the polishing capability of the brush.

[0025] To further enhance the benefit described above it is preferredthat the bristles are longer than the tooth polishing element. By thisis meant that the bristles extend further from the head than does thewall-like member. This creates a recess in the centre of the brush headwhich further allows the flexing of the bristles to effect good cleaningwhile allowing the wall-like member to polish the teeth.

[0026] Preferably the bristles extend from 8 to 14 mm from the brushhead and the wall-like member 6 to 14 mm and preferably 8 to 12 mm, sothat the bristles may be the same length or shorter than the wall-likemember if preferred.

[0027] In a further aspect, the present invention provides for the useof a toothbrush comprising a handle and a head, said head comprisingupstanding bristles and at least one upstanding tooth polishing element,characterised in that the tooth polishing element is in the form of aresilient wall-like member and is flanked by bristles for polishing theteeth.

[0028] The present invention also provides for the use of a toothbrushcomprising a handle and a head, said head comprising upstanding bristlesand at least one upstanding tooth polishing element, characterised inthat the tooth polishing element is in the form of a resilient wall-likemember and is flanked by bristles for whitening the teeth.

[0029] In yet a further aspect the brush according to the inventionprovides for the use of a toothbrush comprising a handle and a head,said head comprising upstanding bristles and at least one upstandingtooth polishing element, characterised in that the tooth polishingelement is in the form of a resilient wall-like member and is flanked bybristles for providing a smooth feel to the teeth.

[0030] The brush according to the invention may be made from anymaterials commonly used in the art.

[0031] Accordingly, the handle and head of the brush can be moulded frompolyolefins such as polypropylenes and polyethylenes, polyamides such asnylons, and polyesters such as polyethylene terephthalate. Othersuitable materials include polymethylmethacrylate, styrene acrylonitrateand cellulose esters, for example cellulose propionate.

[0032] The bristles of the brush may be made from a flexible materialsuitable for use in dental hygiene. Generally, materials suitable forthe bristles are polyamides such as nylon or polyesters such aspolybutylene terephthalate.

[0033] Preferably, the wall-like member is made of a polymer material,such as a block co-polymer. Preferred block copolymers include styrenes(for example styrene ethylene butadiene styrene, or styrene butadienestyrene), polyolefins (for example polypropylene/ethylene propylenediamine modified systems (i.e. synthetic rubber)), polyamides (forexample polyamide (2 or polyamide 6), polyesters (for example polyesterester or polyether ester), polyurethanes (for example polyesterurethane,polyetherurethane or polyesteretherurethane).

[0034] Preferred wall-like member materials can be two phase systems,which contain an internal phase material in a continuous phase ofanother material. A particularly preferred example of this is thepolypropylene/ethylene propylene diamine modified material describedabove, which is commercially available as Santroprene PPA (ex AdvancedElastomer Systems). Such two phase materials may conveniently have acontinuous external thermoplastic phase, with the internal phasetypically containing particles which may be in the order of 0.5-5microns across.

[0035] Alternatively, the material which comprises the wall-like membermay be surface modified by grafting on other polymers to facilitate thebonding of the elastomeric bridge to either the bristle material, or thehandle material, or both.

[0036] Other methods of surface modification of one or more componentsare contemplated to facilitate adhesion of the wall-like member to thehead. For example, compatabilizer materials can be incorporated into anyone of the components of the brush to facilitate its adhesion to anothercomponent.

[0037] Alternatively, one or more components can be chemically modifiedby a chemical surface treatment to facilitate its adhesion to anadjacent component. Alternatively, one or more components can bemodified by surface oxidation (e.g. by flaming, or by electricaldischarge) to facilitate its adhesion to an adjacent component.

[0038] In a preferred embodiment, to facilitate and simplify bonding ofthe wall-like member to the head, the head may be made of materialswhich are of similar or even the same character, so that they forexample have similar functional groups, similar levels of functionality,similar surface energies, and so on. Such similarity may facilitateadhesion of the respective components, and in a preferred embodiment thehead and wall-like member may be made of the same materials, for examplenylon materials.

[0039] Preferred wall-like member materials are thermoplastic elastomersfor ease of injection moulding.

[0040] Embodiments of particular toothbrushes according to the inventionwill now be described in more detail with reference to the followingfigures.

[0041]FIGS. 1a through 1 d show a single brush in various views. FIG. 1ais an elevational view of the head and part of the handle of a brushaccording to the invention. FIG. 1b is a plan view of the brush shown inFIG. 1a. FIG. 1c is an end view of the brush shown in FIGS. 1a and 1 balong direction A. FIG. 1d is a cross-sectional view along section B-Bof the brush shown in FIGS. 1a to 1 c.

[0042]FIGS. 2 through 5 are plan views of various brushes according tothe invention.

[0043]FIGS. 6 and 7 are cross-sectional views of brushes according tothe invention exemplifying the methods for attaching the wall-likemember to the brush head.

[0044]FIG. 1a shows a brush comprising a handle (1) and a head (2). Thehead has a bristle bearing surface 2 a from which extend bristles (3).

[0045]FIG. 1b shows a brush according to FIG. 1 additionally showing anupstanding polishing element in the form of a wall-like member (4). Thewall-like member (4) is only seen in plan view but it clearly runs alonga significant length of the head (2) and, in plan view, appears longerthan the length of the head. The bristles (3) extend further from thehead (2) than the wall-like member (4).

[0046]FIG. 1c shows the wall-like member (4) is attached at its base tothe head (2) and is flanked at either side by the bristles (3).

[0047]FIG. 1d shows the wall-like member (4) attached at its base to thehead (2) of the brush.

[0048]FIG. 2 shows a brush head (2) with a wall-like member (4) andbristles (3). The wall-like member is generally sinusoidal in plan viewand runs generally along a longitudinal axis (L) of the head (2).

[0049]FIG. 3 shows a brush head (2) with a wall-like member (4) andbristles (3). The brush also has further tufts of bristles (3 a) locatedwithin the central area of the head near to the wall-like member (4).

[0050]FIG. 4 shows a brush head (2) comprising two wall-like members,which preferably are linked through a channel allowing for one-stepinjection moulding.

[0051]FIG. 5 shows a brush head (2) comprising three wall-like members(4) which are not curved. The brush head also has a large bristle tuft(3 a) located at the toe of the brush head.

[0052]FIG. 6 shows a cross-sectional view of a portion of a brushaccording to the invention. The figure shows a handle (1) and a head(2), bristles (3) and wall-like member (4), the latter two extendingfrom the bristle bearing surface (2 a) of the head (2). The wall-likemember (4) is contiguous with a portion of the handle (6) via a channel(5) which extends along the neck between the handle and the head. It maybe that the channel is visible, as would be expected with a brushaccording to the figure, or may be hidden. Such a configuration wouldallow the wall-like member and the region around the handle to be formedby injection moulding through a single injection point. Typically, thewall-like member is made from a rubbery material such as a thermoplasticelastomer, e.g. TPE and the region around the handle (6) provides animproved grip.

[0053]FIG. 7 shows an alternative method of attaching the walllikemember to the head of the brush. The wall-like member in this structurehas a base portion (4 a) of greater dimensions than the aperture (6)through which it passes to the surface of the head. A wall-like membersuch as is depicted in this figure may also be made by injectionmoulding.

[0054]FIG. 8 shows a wall-like structure which tapers away from thebristle-bearing surface (2 a) of the brush head (2). By tapered awayfrom the brush head is meant that the wall-like member has a base (4 a)and a tip (4 b) and the distance across the base (B) is greater than thedistance across the tip (T).

[0055]FIG. 9 shows a wall-like member (4) with a ridge (7) running alongthe tip. It may or may not be that the ridge runs along the entirelength of the member.

[0056]FIG. 10 shows a wall-like member (4) which has a textured surface(8). By textured is meant that the surface is rough and this may be dueto the way that the member is formed or due to the inclusion of anabrasive material.

1. Toothbrush comprising a handle and a head, said head comprisingupstanding bristles and at least one upstanding tooth polishing element,characterised in that the tooth polishing element is in the form of aresilient wall-like member and is flanked by bristles.
 2. Toothbrushaccording to claim 1, characterised in that the wall-like member iscurved.
 3. Toothbrush according to claim 1 or 2, characterised in thatthe wall-like member runs in a generally sinusoidal fashion along alongitudinal axis of the head.
 4. Toothbrush according to any precedingclaim, characterised in that the wall-like member is made of a materialof Shore A hardness between 5 and
 80. 5. Toothbrush according to anypreceding claim, characterised in that the wall-like member is taperedaway from the head.
 6. Toothbrush according to any preceding claim,characterised in that the wall-like member is textured.
 7. Toothbrushaccording to any preceding claim, characterised in that the wall-likemember has at least one ridge running along at least part of themember's length.
 8. Toothbrush according to claim 7, characterised inthat the ridge runs along at least part of the tip of the wall-likemember.
 9. Toothbrush according to any preceding claim, characterised inthat the wall-like member contains abrasive material.
 10. Toothbrushaccording to any preceding claim, characterised in that the bristles arelocated outermost on the head.
 11. Toothbrush according to any precedingclaim, characterised in that the bristles extend further from the headthan does the tooth polishing element.
 12. Use of a toothbrush accordingto any preceding claim for polishing the teeth.
 13. Use of a toothbrushaccording to any of claims 1 to 11 for whitening the teeth.
 14. Use of atoothbrush according to any of claims 1 to 11 for providing a smoothfeel to the surface of the teeth.